rac-Methyl (1R,3′S)-1′,1′′-dimethyl-2,2′′-dioxo-2H-dispiro[acenaphthylene-1,2′-pyrrolidine-3′,3′′-indoline]-4′-carboxylate

Abstract

In the title compound, C26H22N2O4, the pyrrolidine ring adopts a twisted conformation and the other five-membered rings adopt envelope conformations with the spiro C atoms as the flap atoms. The naphthalene ring system of the dihydroacenaphthylene group forms dihedral angles of 89.2 (9) and 75.5 (6)° with the pyrrolidine and indole rings, respectively. The pyrrolidine ring makes a dihedral angle of 80.1 (9)° with the indole ring. In the crystal, molecules are linked by weak C—H...O hydrogen bonds, forming chains along the b-axis direction.